Linguistic Validation and Cross-Cultural Adaptation of the Liverpool Osteoarthritis in Dogs Instrument for the German- and Spanish-Speaking Populations.

The Liverpool Osteoarthritis in Dogs (LOAD) is a widely used observer-reported outcome measure questionnaire for assessing pain in dogs with osteoarthritis. This study aimed to linguistically validate and culturally adapt the LOAD for German- and Spanish-speaking populations.The process followed the Functional Assessment of Chronic Illness Therapy translation methodology and involved two forward translations, a reconciliation of the forward translation, back translations, expert reviews, and cognitive debriefing interviews with a representative sample of dog carers. A universal approach was adopted to generate Universal German and Universal Spanish versions of the LOAD suitable for use in all German- and Spanish-speaking countries.The two forward translations and the reconciliation phase showed 12 and 6 discrepancies for the German and Spanish LOAD, respectively. Comparing the backward translation with the original version identified 13 items or instructions in the German LOAD and 20 in the Spanish LOAD that required retranslation. The review panel resolved both conceptual and literal discrepancies, while input from cognitive interview participants contributed to 6 additional revisions for the Universal German version and 15 for the Universal Spanish versions of the LOAD.This stepwise approach resulted in linguistically validated and culturally adapted universal versions of the LOAD for the German- and Spanish-speaking populations.